Patients will be followed-up after discharge from hospital for net adverse events up to 1 year after enrolment by scheduled telephone interviews and outpatient visits. Interviewers will be blinded to the randomization scheme and to the results of platelet aggregation. An independent Clinical Event Committee, composed of 3 cardiologists and 1 neurologist and blinded with respect to randomization allocation will review and adjudicate the occurrence of each suspected clinical end point. Interim analyses of efficacy and futility, using O'Brian-Fleming guidelines for group sequential design, are planned when one fourth, one half and three fourths of the maximum number of the 632 patients had been followed-up for 30 days. Interim analyses and all safety data will be reviewed by an independent Data Safety and Monitoring Committee, composed of a chairman, a statistician, and 2 physician members.